Method of manufacturing plate-glass devices.



M. A. ROSS. METHOD 0E MANUFACTURING PLATE GLASS DEVICES.

PQ" APPLICATION FILED JULY 31, 1912.

D L@ /jQ 2 SHBETS-SHEET 2. FW@ I Patented 00E. M, 1913.

' ing plate glass devices,

narran enanas renna eraan MYRON A. ROSS, 0F MORGANTOWN, VTEST VIRGINL, ASSEGNUR '0 BRESSED PRISM PLATE GLASS COMPANY, 0F MORGANTOWN, WEST VERGINI, CQRPQMTION 0E' WEST VIBGENIA.

METHOD OF MANUFACTURING PLATE-GLASS DEVICES.

Specicaton of Letters atent.

Application filed July 31, 1912.

Patented @et te, laag, serial no. 712,447.

To all whom it may concern.'

Beit known that I, MYRON A. Ross, a citizen of the United States, residing in Morgantown,.in the county of Monongalia and State of West Virginia, have invented a new and useful improvement in Methods of Manufacturing Plate-Glass Devices, of which the following is a specification.

This invention relates to improvements in method of manufacturing plate glass devices.

An object of the invention is to provide a method or process for manufacturing plate glass devices, particularly of large size, such as are adapted for illuminated, display, changeable sign use, and in which the letter, numeral, emblem or other symbol is formed with sharp, clear voutlines and integrally with the plate, the entire glass-mass being substantially homogeneous throughout.

Another object of the invention is to provide a method or process of'manufacturing plate glass devices having the entire glassmass homogeneous throughout and having the letter, numeral, emblem or other symbol in protuberant relief, relatively thick as compared to the thickness of the plate, the raised portion, per se, being preferably one and one half, or'even more, times as thick as the plate, and in which the symbol in some instances is made lens-form, and forms with the plate a substantially plano-convex lens adapted to disperse and distribute light rays passing through the glass, the portions 4in relief Ibeing preferably lluted longitudinally to thereby subdivide thelarger lens into a plurality of smaller lenses in order that the shaft of light, as it einer es or is reflected from the plate glass device, substantial Width.

A further object ofthe invention is to n'ovidc a method or process of manufacturin which the letter, numeral, emblem or other symbol is formed wholly within, and has all portions removed from, the edges of the plate.

'lhe invention furthermore consists in the improvements in the steps and in the novel combination of the ste s of the process as more fully disclosed ereinaftfer and set forth in the claim.

l am aware that it has been customary hitherto to form letters and' numerals on may be given blocks by lacing a gathering of glass in a mold an bringing a plunger down upon it, but it has been found that this method of manufacture is not practicable` for making such articles of large size, .the articles being limited generally to not more than three or four inches square. The finished article, even when the best results are obtained by this ordinary process of molding, lacks strength, is apt to be cracked, and when cut will break upon Yirregular lines, due to the inherent strains caused by the pressing step. I am aware, also, of a method of manufacturing prism glass by a process involving thc two operations of tirst forming a sheet of glass, and secondly exerting pressure in a direction transverse to the plane of the sheet to form a plurality of prisms, regularly arranged over as illustrated for instance in the patent to Ripley et al. No. 651,025, issued October 30th,' 1900. In carrying out the process disclosed in this patent after the glass plate or sheet has been formed, thesame is placed between a platen and a die, the latter having a plurality of closely arranged, equally spaced, parallel ribs, which results in producing an article havinga regular or conventional design.` Prism .Glass has also been made by the Ripley et a. process, having the ribs, ridges or prisms arran ed both longitudinally and transversely o the plate in a conventional manner. But in all such instances, the glass plate is subjected substantially uniformly throughout its entirety to regularly distributed and equalized stresses and variations of temperature, the quantity of the glass-mass which goes to make up each rib or prism is comparatively small, each portion is only slightly displaced from its original position in the late, and furthermore, the movement of t e portion displaced is in paths practically uniform throu hout, and without the thickness of the p ate being greatly diminished.

In manufacturing plate glass devices having protuberant letters, numerals, emblems or other symbols, the redominant characteristics of which are t eir irregularity and diversity of outline and arrangement, it is necessary to displace some portions of the glass-mass relatively great distances and other portions only short distances, in d ithe entire surface of the sheet,

` self-confined by the less stantially verse paths all 'substantially convergent toward andl into the protuberant symbol be-V ,ing formed, and the quantityy o f the glassmass required at one point is, 1n some instances, several times more than that required at another point, yetl throughout all this irregular y and uneven displacement, both as regards lquantity and movement, and uneveny variations of temperature and stresses at different portions of the plate, the chemical and physical homogeneity of the ent-ire mass of glass and symbol must be substantially preserved. This result I accomplislr by my process described herein. e

In my process I first form a sheet or plate of glass ypreferablyby placing a gathering of glass on a platen'andgiredu'cing it to plateorm in a state of what I term homogeneous consistency and molecular arrangement, as by'a rolling or equivalent operation. In practice this is .preferably done by rolling theglass while freely the Well known manner, and then while the plate is on a platen,which may or may not be the platen upon which the gathering is rolled,a'pply pressure in a direction transversevto the plate on portionslocated outside of the periphery of the letter 'or other symbol formed on the plate, and thus decrease the thickness of the plate at the porcause portions of the glass-mass to How to.

ward the center or part of the plate where the letter or other symbol is located, the flow of the glass-mass taking place in paths subplate and convergent toward the part where the letter or 4other symbol is ormed, so that portions of the glass-mass a e then forced up into and completely fill a deep recess ina die corresponding to the letter or other symbol desired. During this operation the edges of the desirable. In practice thfay are or may be viscosity of the sheet at or near its somewhat cooler outer edges, which impedes the outward iiow of the glass and causes it to flow inward and into the recess of the die. The plate with the letter or other symbol formed integrally therewith is then allowed to chill sllghtly to cause it to set suciently to be able to retain its shape, after which the plate glass device is annealed in the ordinary manner. In practising my invention, I may make the plate comparatively thin and the symbols, formed integrally therewith, relatively thick, and the height of the letters, numerals or other symbols may about eight to eighteen inches, and may be made evenhigher. If desired, the number of letters, numerals or other symbols on a single plate may be increased or multiplied so as to form, for instance, a complete word,

composing the platel plastic, in

paralleling the surface of thel plate may be confined as foundV range from indicated by the arrows a, a in rolled plate on which the symbols are formed, which can, in -actual practice, be

made as large as sixty by the finished plate having proximately five-sixteenths of an inch, and the solid symbols being approximately a further' one-half inch in thickness.

In the drawing forming a part of this specification, Figure l is a plan .view of a plate glass device, made by my process. Fig. 2 is a side elevation of the device shown in Fig. 1. Fig. 3 is an enlarged, detail, sec tional view, approximately full size, and taken substantially on the line 3-3 of Fig. 1. Fig. 4 is a plan view of the plate or sheet showing thereon, in outline only, a letter such, as is adapted to be made by my process, and illust-rating, rows, the direction of ow glass-mass, and Fig; 5 is a sectional View, taken on the line 5-5 of Fig. 4, showing, in dotted lines, the original thickness of the plate before the pressing operation takes place, and also indicating, by arrows, the paths followed by portions of the glassmass during the pressing operation.

In the drawing, 10denotes a rolled, rectangular ate'having a plane back surface and whicli, as shown, is provided with a single, raised, solid symbol 11, formed integrally with the plate, the glass-mass of both members being substantially homogeneous throughout. The particular symbol shown in the drawing is the letter F but, as will be understood, other letters of the alphabet, punctuation marks, numerals, emblems or,` other symbols could be formed withoutv departing from the spirit ofthe invention. Each portion of the raised symbol 11 is substantially lens-form, vided with a plurality of convex flutes or ninety-six inches,

of portions of the ribs 12 arranged longitudinally of each pory tion of the symbol.

The plate shown in the drawing is provided with only a single letter, and is adapted to be used in combination with a number of other plates similarly provided with letters for usein making up illuminated display signs, the letters of which are approximately one foot in height, although, as will be obvious, a single plate may be made with a plurality of letters or other symbols formed' thereon, if desired.

After the plate or sheet is -formed, pressure is applied to the same at portions surroundin the outline of the letter or other symbol eing formed and at all such portions simultaneously, if desired, which will cause portions of the glass-mass to flow in diverse, substantially convergin paths, as ig. 4. In

of the finished arby the size of the a thickness 'of ap-I by means of ar-l and is promaw/Q11;

doing this a die haring a recess eut therein on its lower face, corresponding to the letter or other symbol desired to be formed, is placed over the plate and as the pressure is continued on the portions of the plate surrounding the symbol, the thickness of the plate will be diminished, as shown in Fig. and displaced portions ot' the glass-mass will be caused to flow'in the paths, as indicated by the arrows Z), the recess in the die corresponding to the symbol, it being apparent that the quantity of glass displaced from the portions of the plate surrounding the symbol will approxi-y mate the quantity of glass required to till the recess in the die to form the symbol. After the squeezing or pressing operation, the entire glass-mass is allowed to cool a sullicient time,-generally two or three seconds,-to cause the glass-mass to set, so that it may be properly handled and transferred to the annealing ovens without becoming distorted.

I claim 4 i The herein described process of makingv Z), up into and to fill 5 forming a protuberant symbol upon one sur- 1 face ot the sheet and integral and homogeneousl therewith, by reducing the thickness of the sheet and causing the lass of the body of the saine to flow, for various distances and in various amounts as may be required by the irregular configuration of the symbol, in convergent directions and ulti mately out from the surface of the sheet to forni such symbol; and at the same time forming around the symbol an area of sheet glass of substantially uniform thickness; substantially as specified.

ln testimony whereof, l have vhereunto set my hand in the presence of tWo subscribing Witnesses.

' MYRON A. ROSS. Witnesses:

HENRY LOVE CLARKE, JOSEPH HARRIS. 

